Evenden J L, Turpin M, Oliver L, Jennings C
Merck Sharpe and Dohme Neuroscience Research Centre, Harlow, Essex, UK.
Psychopharmacology (Berl). 1993;110(1-2):169-76. doi: 10.1007/BF02246968.
Psychomotor stimulant drugs such as caffeine, nicotine, amphetamine and cocaine, have been shown to improve vigilance in man under conditions of fatigue. Nicotine has also been shown to improve performance in some cognitive tests in patients with Alzheimer's disease. In rodents these drugs increase activity which may confound "performance enhancing effects" in rodent models. However, improvements have been found in a number of tests that do not seem to be directly dependent upon an enhancement of locomotor activation. In one example, Evenden and Robbins (1985) reported consistent improvements in a visual tracking test following amphetamine. The present study was undertaken to determine whether these performance enhancing effects of amphetamine could also be obtained with cocaine and apomorphine, which both have psychomotor stimulant effects through their actions as, respectively, indirect and direct dopamine agonists, and by caffeine and nicotine, which do not have a direct dopaminergic mechanism of action. The results of the study indicate that all five drugs improved tracking performance at one or more doses. The most consistent effects were obtained with amphetamine which, like cocaine and nicotine, improved tracking at a dose which did not produce other changes in behaviour. Taking into account previous studies (Evenden and Robbins 1983, 1985), these results were interpreted as indicating that psychomotor stimulant drugs produce a general activation of behaviour. At all but the highest doses of such drugs, the form of behaviour that is observed depends upon the environment.(ABSTRACT TRUNCATED AT 250 WORDS)
精神运动性兴奋药物，如咖啡因、尼古丁、苯丙胺和可卡因，已被证明在疲劳状态下可提高人的警觉性。尼古丁还被证明能改善阿尔茨海默病患者在一些认知测试中的表现。在啮齿动物中，这些药物会增加活动量，这可能会混淆啮齿动物模型中的“性能增强效应”。然而，在一些似乎并不直接依赖于运动激活增强的测试中发现了改善。例如，埃文登和罗宾斯（1985年）报告称，服用苯丙胺后，视觉跟踪测试有持续改善。本研究旨在确定可卡因和阿扑吗啡是否也能产生苯丙胺的这些性能增强效应，可卡因和阿扑吗啡分别作为间接和直接多巴胺激动剂发挥精神运动性兴奋作用，以及咖啡因和尼古丁是否也能产生这种效应，因为它们没有直接的多巴胺能作用机制。研究结果表明，所有这五种药物在一个或多个剂量下都能改善跟踪性能。苯丙胺的效果最一致，它与可卡因和尼古丁一样，在不产生其他行为变化的剂量下就能改善跟踪性能。考虑到之前的研究（埃文登和罗宾斯，1983年、1985年），这些结果被解释为表明精神运动性兴奋药物会产生行为的普遍激活。除了这些药物的最高剂量外，观察到的行为形式取决于环境。（摘要截取自250字）
